Roller metal pin for use as electric connector or fastener

ABSTRACT

There is disclosed a springy rolled metal pin such as a spirally rolled pin, the inner end portion of which is bent inwardly to form a springy tongue dividing the interior of the pin into two chambers. Upon insertion into one of the chambers of a wire of suitable diameter which may be part of an integrated circuit module, and subsequent insertion of the pin into a confining mounting hole, the wire is tightly held in the respective pin chamber by the lateral pressure of the tongue and the radial pressure exerted by the inner peripheral wall of the pin, said radial pressure being caused by the diametrical contraction experienced by the pin when inserted into the mounting hole. There is also disclosed a springy rolled two-part or double pin, the two parts of which have different diameters. When one part of such double pin is inserted into a confining mounting hole, the inserted pin part anchors itself in the hole due to its springiness while the protruding part retains its springiness and is available, for instance, as a springy male contact element for making connection with a tubular female contact element or with the foil conductors on printed circuit boards or with a tubular female.

United States Patent Aug. 29, 1972 Modreyv [54] ROLLER METAL PIN FOR USE AS ELECTRIC CONNECTOR OR FASTENER [72] Inventor: Henry John Modrey, 158 Eagle Dr.,

' Stamford, Conn. 06903 [22] Filed: Aug. 13, 1968 [21] Appl. No.: 752,329

[52] US. Cl. ..339/258 R, 339/17 C, 339/ 17 CF, 339/17 L, 339/95 D, 339/176 MP, 339/256 R [51] Int. Cl. ..H0lr 11/00 [58] Field of Search ..339/258, 256, 221, 17

[56] References Cited UNITED STATES PATENTS 667,421 2/ 1901 Blackman ..339/94 A X 3,158,425 11/1964 Pn'tulsky ..339/22l X FOREIGN PATENTS OR APPLICATIONS 1,507,524 ll/l967 France ..339/256 1,018,125 10/1957 Germany ..339/256 260,060 10/ 1926 Great Britain ..339 /156.1 942,835 1l/1963 Great Britain ..339/256.5

Primary Examiner-Richard E. Moore There is disclosed a springy rolled metal pin such as a spirally rolled pin, the inner end portion of which is bent inwardly to form a springy tongue dividing the in terior of the pin into two chambers. Upon insertion into one of the chambers of a wire of suitable diameter which may be part of an integrated circuit module, and subsequent insertion of the pin into a confining mounting hole, the wire is tightly held in the respective pin chamber by the lateral pressure of the tongue and the radial pressure exerted by the inner peripheral wall of the pin, said radial pressure being caused by the diametrical contraction experienced by the pin when inserted into the mounting hole. There is also disclosed a springy rolled two-part or double pin, the two parts of which have different diameters. When one part of such double pin is inserted into a confining mounting hole, the inserted pin part anchors itself in the hole due to its springiness while the protruding part retains its springiness and is available, for instance, as a springy male contact element for making connection with a tubular female contact element or with the foil conductors on printed circuit boards or with a tubular female.

4 Claims, 15 Drawing Figures Patented Aug. 29, 1972 FIG. I4

ROLLER METAL PIN FOR USE AS ELECTRIC CONNECTOR R FASTENER This invention relates to springy hollow pins and more particularly to hollow cylindrical springy pins spirally wound in several layers from a strip of sheet metal, or rolled in one layer from a strip of sheet metal.

Rolled springy pins of the types above referred to are widely used as mechanical fasteners by inserting the pins into holes of slightly smaller peripheral outline than the outer peripheral outline of the pins in the relaxed condition thereof. A pin inserted into such confining hole is radially compressed and accordingly exerts a continuous radial outward pressure upon the side wall of the mounting hole, thereby being anchored in the same.

Modern mass production techniques permit economical precision manufacture of miniaturized springy hollow pins of the kind above referred to with diameters of one millimeter, or less. Such pins would appear to be eminently suitable, if made from suitable conducting material, as contact elements in miniaturized electrical circuit components.

If spirally wound pins are used in lieu of the conventional tubular contact pins, they offer certain advantages due to the fact that the edge of the outermost convolute of the material projects slightly from the round cross-section and thereby forms a sharp longitudinal edge. This edge is pre-eminently suitable as a primary spring contact surface, if the pin is inserted into a tubular female contact. Moreover, the edge is capable of cutting through a dirt or oxide film on the corresponding female contact element when the pin is inserted. This feature is especially valuable when the pin contact is used in connection with aluminum, for instance in a grounding connection, since aluminum is prone to develop surface oxides which are insulating.

The conventional methods of connecting wires to pin contacts are by soldering or crimping. It is however possible to utilize the pin itself as the wire attaching means when the pin is a hollow springy pin. As on insertion of each pin into a confining mounting hole its diameter is reduced, it is feasible to insert a wire, the diameter of which corresponds to the inner diameter of said pin in its non-inserted configuration and which is firmly gripped when the pin diameter decreases upon insertion of the pin into the mounting hole. However, it has been found that this method of connecting a wire is unsatisfactory. In the first place, the wire is difficult to insert since its diameter is practically that of the bore of the pin. In the second place, a wire attached by this method is subject to damage. A rolled pin when forced into the mounting hole becomes for all practical purposes a rigid tube without appreciable resiliency. A wire pushed into the pin prior to the insertion of the pin into the mounting hole may be strongly held in the pin, but the pressure exerted by the now substantially rigid walls of the pin upon the wire is likely to cause a gradual deformation of the wire to an extent such that the physical strength of the wire is seriously affected.

As is well known, a copper wire when subjected to tightening at a localized area is in effect subjected to cold working. As a result, the wire builds up a hardness which reduces its tendency to recover its original shape, and the wire tends subsequently to break at the point where it emerges from the pin. As is well known,

a wire remaining under strong compression rapidly develops cold flow and will collapse and embrittle gradually. As is evident, this adversely affects the contact quality of the connection between the wire and the terminal constituted by the pin, and eventually endangers the mechanical continuity of the conductor.

It is a broad object of the invention to provide a novel and improved pin of the general kind above referred to which when used as an electric connector or terminal exhibits entirely satisfactory contact-making qualities. More specifically, the electric contact obtained with a rolled pin according to the invention has been found to exert constant and substantially uniform elastic pressure, resulting in excellent contact quality,

even under severe operating conditions, with no tendency towards pressure-embrittlement of the conductor wire. This contact is essentially effected by the projecting edge of the pin which also acts as an oxide cutter, as above stated.

Extremely small pins of the kind herein referred to can be economically and accurately produced. In miniaturized pin connectors of conventional design, the pins are non-yielding and the required contact pressure is effected by the female contacts which are, in fact, small leaf springs. As is well known, very small leaf springs have little resiliency, and this lack of resiliency in the female contacts limits the miniaturization of multiple pin connectors. Accordingly, the invention makes available miniaturized pin connectors in which the required resiliency resides in the rolled contact pins which makes it possible to employ non-resilient female contacts without leaf springs.

Further the invention makes available miniaturized wiring terminals for pin contacts which require neither soldering nor crimping of the conductor but connect the wire automatically upon insertion of the pin contact into its base.

It is also an object of the invention to provide a novel and improved pin of the general kind above referred to which when used either as a mechanical fastener or as an electric connector or terminal clamps a member such as a wire inserted thereinto with a tight grip without damaging the inserted member.

Another more specific object of the invention is to provide a novel and improved pin of the general kind above referred to in which a springy clamping pressure distributed over substantially the entire length of the inserted member is obtained by dividing the interior of the pin into two lengthwise chambers by means of an inwardly bent-off portion of the sheet material from which the pin is formed. As is evident, such end portion being freely deflectable within the pin will retain its springiness after the pin is diametrically compressed by being inserted into a confirming mounting hole. A member inserted into either one of said chambers is retained essentially by the transversely directed pressure of the springy bent-off portion.

As is evident, the pin when anchored in the mounting hole and tightly gripping a wire with practically constant contact pressure, constitutes in effect a solderand crimpless wiring terminal.

It is also an object of the invention to provide a novel and improved pin which comprises two parts rolled with different diameters and can be automatically anchored in a support by inserting one of the pin parts into a confining mounting hole formed in the support. While the inserted pin part of such double pin loses its elasticity as previously explained, the other part retains the same and may thus be utilized as a male contact element which, when inserted into a rigid female contact sleeve, will make good electric contact with such sleeve due to the springiness of the respective pin part. The inserted and substantially rigid pin part may be used as a conventional soldering or crimping terminal. It may also be provided with an internal springy tongue which will safely grip a wire or similar member pushed into the respective pin part prior to the insertion thereof into a confining mounting hole as previously explained.

The double pin as described can be advantageously used for securing two circuit components to each other so that the pin always remains in the selected one of the two components when the same are separated. This feature makes it possible to simplify the design of electrical multi-pole connectors. In conventional connectors, the pin elements must be firmly anchored in their base. This is done by molding the pins into the base, or

else by providing the pins with a projection which engages an undercut inside its mounting hole. Undercuts of this type are difficult to form in molded components, and generally require the base to be made from two parts which are clamped together. A contact pin according to the invention requires nothing but a smooth seating hole for attachment of the pins. However, if such pins would subsequently engage female contacts, it is a matter of accident whether on separation of the connector the pins would remain in theirmounting holes or in the female contacts. With a double pin according to the invention, it is easy to arrange that the mechanical attachment force of the pin is much stronger than its contact pressure. This pressure differential insures that all contact pins remain in situ when the connector is separated.

The differential retention force of a double pin as just described can be also advantageously used when the pin is used as a mechanical fastener for detachably joining two parts and it is desired that the pin always remains in the same part when the two parts are separated.

It is a further object of the invention to provide a novel and improved multiple connector for simultaneouslyand detachably connecting a plurality of foil terminals of a printed circuit board to external terminals which in turn are available for making further connections.

A more specific object of the invention, allied with the next preceding one, is to provide a novel and improved printed circuit connector in which a plurality of double pins as hereinbefore referred to are mounted on an insulation body so that the foil terminals to be connected are automatically engaged by the double pins with a frictional pressure grip when the connector is applied to the printed circuit board, thereby assuring high contact quality and permitting easy simultaneous assembly and disassembly of the multiple connections.

Other objects, features and advantages will be pointed out hereinafter and are set forth in the appended claims constituting part of the application.

In the accompanying drawing, several preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

In the drawing:

FIG. 1 is a perspective view of a spirally wound pin according to the invention, with a wire end inserted into one of the chambers of the pin;

FIG. 2 is a cross-sectional view of the pin according to FIG. I, inserted into a confining mounting hole;

FIG. 3 is a perspective view of a single layer rolled pin according to the invention, with a wire end inserted thereinto;

FIG. 4 is a sectional view of a pin according to FIG. I, inserted into a confining mounting hole and having several wires and connecting elements attached thereto;

FIG. 5 is a perspective view of an integrated circuit module and a mounting base therefor, the module and the base being shown separated from each other;

FIG. 6 shows one of the pins on the mounting base on an enlarged scale;

FIG. 7 is a perspective view of the module and the mounting base of FIG. 5 in assembled position;

- FIG. 8 is a perspective view of a double pin having a firmly wound portion and a loosely wound portion;

FIG. 9 shows a sectional view of a double pin according to FIG. 8 used as a circuit component of a multipoleconnector;

FIG. 10 is a perspective view of a double pin with an integral contact flag inserted into a printed circuit board;

FIG. 10a is a sectional view taken on line l0a-l0a of FIG. 10;

FIG. 11 is a blank for rolling double pins according to FIG. 8;

FIG. 12 is an exploded perspective view of a printed circuit connector using double pins according to the invention;

FIG. 13 is a sectional plan view of the printed circuit connector taken on line 13 13 of FIG. 12, in engaged position; and

FIG. 14 shows a double pin used as a pull-off fastener for connecting two elements.

Referring first to FIGS. 1 and 2, the hollow cylindrical pin as exemplified in these figures is formed by spirally winding a springy metal strip 1. Three convolutes are shown, but there is no limitation as to the number of convolutes that may be used. The inner end la of the metal strip is bent off into the interior of the pin to define therein two chambers 2 and 3. The tongue formed by the bent off strip may terminate short of the inner wall of the pin, or it may be bent over as shown at 10 in FIG. 2 for the same purpose. Either way, the tongue is free to flex about its bending edge lb. Accordingly, it is the flexibility of the tongue at the bending edge which primarily determines the force of the spring action of the tongue. The tongue has a flat or curved lengthwise configuration, but an S-shaped configuration has been found to be particularly advantageous and such configuration is shown in FIGS. 1 and 2.

FIG. 2 shows the pin fitted into a confining mounting hole 5 in a support 6. The support may be visualized as, for instance part of a metal support if the pin is used as a mechanical fastener, or as part of a plastic insulator if the pin is to be used as an electric connector. As previously explained, a spirally wound springy pin, as shown in FIG. 1, when inserted into a confining mounting hole that is, a hole the inner diameter of which is slightly larger than the outer diameter of the pin is firmly retained in the mounting hole due to the radially outward pressure of the springy pin walls. As also previously explained, the pin after it is inserted into the hole, becomes a rigid tube for all practical purposes.

Let it now be assumed that the pin is to be used as an electric connector and that the stripped end 8 of a wire conductor 9 is to be connected to the pin. To effect such connection, the wire end 8 is pushed into one of the chambers as defined in the pin by tongue 1a, insertion of the wire into the chamber 3 being shown. The diameter of the pushed-in wire end should preferably be such that the wire is slightly held by engagement with tongue 1a. The pin with the wire inserted thereinto is now forced in the confining mounting hole causing a corresponding contraction of the pin and thus a decrease of the clearance available therein for the wire. As a result, the wire is now subjected to the radially inward pressure of the respective inner wall portion of the pin and to the pressure of the flexible tongue so that it is safely held between the tongue and the inner wall of the pin. The pressure exerted by the tongue is independent of and in a plane other than the radial pressure exerted by the engaged inner wall surface of the pin. As is evident, the pressure exerted upon the wire is not at a localized area of the wire, but along the entire length of the tongue which is in engagement with the wire, and

similarly, along the entire length of the inner wall surface of the pin against which the wire is pressed by the tongue. As can be best seen in FIG. 2, the areas of engagement between the wire and the tongue are further increased by the S-shaped configuration of the tongue.

A second wire can be similarly inserted into chamber 2. Moreover, two further wires can be inserted into the chambers from the opposite end of the pin due to the independent springiness of the tongue la.

The pin of FIG. 3 uses the principle of FIGS. 1 and 2, but is simplified in that a strip 10 of springy sheet metal is rolled to form a hollow single convolute pin, lengthwise slotted at 11. One end of the strip is inwardly bent to form a tongue 10. The tongue is shown to be flat and to terminate short of the inner wall of the pin, but of course it can also be S-shaped or similarly curved and be bent over at its outer edge, as is shown at 10 for tongue 1a. Tongue 10a defines two chambers 12 and 13 within the pin. Stripped wire end 8 of conductor 9 is shown inserted into chamber 13 and retained therein as previously described. As also previously described, the spring force of the tongue is primarily controlled by the springiness at the bending line 10b.

FIG. 4 shows a connector pin according to FIG. 1 inserted into a wiring panel 15 made of insulation material. The stripped ends 16 and 17 of the two wire conductors 18 and 19, respectively, are inserted into the connector pin prior to the insertion of the pin into the confining mounting hole 20 in the panel. A ring terminal 21 on a wire conductor 22 is fitted upon the protruding end of the pin. In addition, a solid tip plug 23 may be inserted into and removed from one of the chambers of the connecting pin which serves in this instance as a resilient female contact. The expansion of the connector pin as caused by the insertion of the tip plug retains the terminal ring on the connector pin and effects pressure contact between the connector pin and the terminal ring.

A hybrid multi-purpose connector of this type will be rarely used in industrial practice, but is shown here by way of multiple exemplification.

Insertion or removal of the tip plug will not appreciably affect the retention of wire ends 16 and 17 as the tongue within the pin has inherently sufficient give to permit independent clamping at the top and the bote tom of the connector pin. Moreover, since the pin of the tip plug is solid, it can be readily pushed into an already confined connector pin and can also be removed therefrom when desired, unlike a flexible wire.

Referring now to FIGS. 5, 6 and 7, FIG. 5 shows an integrated circuit module 25 from which extend a plurality of contact wires 26 bent off at their ends 260. The module is designed to be assembled to a mounting base 30. This base carries connector pins 31 of the type shown in FIG. 1 and made of an electrically conducting material. Pins 31 are initially fitted only with their tips into mounting holes in base 3 so that the pins are located but are not confined and thus not radially compressed by the mounting holes. The ends 26a of contact wires 26 are now fitted into one of the chambers of the loosely fitted pins 31, as previously described.

FIG. 6 shows one of the connector pins 31 of the base 30 on an enlarged scale. The pin is optionally provided with a notch 32 for a purpose which will become apparent from the subsequent description.

To complete the assembly, all the pins 31 with the wire ends 260 inserted thereinto are simultaneously pressed down into the mounting base. Accordingly, they are now confined in the mounting holes and thus all the wires are gripped simultaneously in secure mechanical and electrical engagement.

FIG. 7 shows the finished assembly. As can be seen, notches 32 facilitate sufficiently deep insertion of wire ends 26a into pins 31. Moreover, the optional notches permit the use of a very simple insertion fixture capable of pressing down the pins without damaging the wires inserted therein. An enlarged flange at one extremity of pins 31 would serve the same purpose.

As is shown in FIG. 7, the pins protrude from the bottom side of the mounting base for making connections to external circuit components. The protruding pin portions, being integral parts of pins inserted into a confining mounting hole, are substantially rigid as previously explained. They may be utilized as soldering points which are pushed through openings in the conducting foil on a printing circuit board for connection by dipping the entire circuit board into liquid solder. They may also be used as male connector pins for insertion into female contact elements.

In the previously described embodiments of the invention the different springy pressures acting upon the wire conductor or conductors inserted into the chambers of the connector pins are derived from a single spirally rolled pin by the provision of a tongue which constitutes the wire grip proper. The invention also contemplates to derive different spring pressures within one single pin, by providing different configurations at different parts of the pin. Pins of this type are in effect Double Pins with respect to configuration and function and are exemplified in the figures now to be described.

FIG. 8 shows a double pin 35, a part 36 of which forms a hollow pin portion loosely wound from a springy metal strip. The other pin part 37 has a smaller diameter than pin part 36 and is more tightly wound from the same strip. One of the pin parts such as the part 37 may be formed in the manner described in connection with FIGS. 1 or 3, that is, with a tongue dividing the pin part 37 into two chambers.

As shown in FIG. 9, a pin according to FIG. 8 is anchored in an insulating base 41 by pushing narrow part 37 of the pin into a confining mounting hole 40.

If the pin part 37 is formed with a tongue 37a, the stripped end 42 of a wire conductor 43 may be first pushed into one of the chambers in pin part 37. As previously described, wire end 42 is mechanically and electrically retained in pin part 37. Upon insertion thereof into hole 40 which as previously described causes a radial contraction of the pin part and also renders the same substantially rigid. In the event pin 37 is formed without a tongue, the projecting pin part may be utilized as a conventional soldering or crimping terminal.

Pin part 36 retains its inherent springiness as it protrudes from-panel 41 in its entirety and can thus be used to receive a solid contact sleeve 44 thereupon. The inner diameter of sleeve 44 should be visualized as being somewhat smaller than the outer diameter of pin part 36 in the relaxed condition thereof. As a result, the radially outward pressure of part 36 when confined in sleeve 44 retains the sleeve on the pin part with a springy frictional grip.

The frictional retention force between pin part 37 and panel 41 should be correlated with the frictional retention force between pin part 36 and sleeve 44 so that the retention force between pin part 37 and panel 41 is the larger one, thereby assuring that the pins remain in the panel when an axial pull is applied to sleeve 44 for detaching the same from pin part 36. Such correlation can be readily obtained by suitably selecting the relative winding tensions of the pin parts.

Referring now to the connector of FIGS. and 10a, these figures show a double spirally wound pin 50 of the general type shown in FIG. 8, that is, a pin having a narrow part 51 and a wide part 52. The outermost convolute of wide pin part 52 is partly slotted and bent outwardly to form a contact flag 52a. The narrow pin part is forced into a confining mounting hole of a printed circuit board 53 so that the flag 52a is in pressure engagement with one of the foil terminals 54 and 54a respectively on each side of a two-sided circuit board 53 thereby establishing an electric connection with this terminal. As the flag is formed of a single thickness of material and therefore very thin, it will bite somewhat into the material of the foil and will also become slightly bent up at its corner upon insertion of the pin,

.as is shown at 52b. It will maintain this bent up but elastic configuration as the pin is firmly anchored in the printed circuit board, and will constitute an additional contact of high electrical quality.

A pin as shown in FIGS. 10 and 10a provides three different independent springy actions, to wit, the spring action of the upper half of the pin, of the lower half and of the flag. If pin part 52 is formed with a tongue as shown in FIGS. 1 and 3, a fourth spring action is provided, which is independent from the aforelisted three spring actions. As is evident from the previous description, all four spring actions perform useful though different functions.

The connector elements of FIGS. 10 and 10a have the advantage that they automatically compensate for shrinkage of panel 53. Panels of printed circuit boards are generally made of a plastic, and plastic has an unavoidable tendency to shrink in aging. Such shrinkage has caused a serious problem as to making permanently reliable and substantially electrically constant connections between the foil connectors on the board and external circuit components from the beginning of the printed circuit art. Many solutions have been proposed, such as eyelets or plated-through-holes connections, but it has been found that these known connecting means are not permanently satisfactory.

A pin according to the invention and as shown in FIGS. 10 and 1011 when inserted into the mounting hole will automatically and tightly engage the connector foils either on one or both sides of the panel, as the case may be, thereby establishing initially a high quality contact. Subsequent shrinkage of the board does not affect the affixed metal foils nor the position of the board which is supported by the foil. As a result, the initially cylindrical mounting hole 53a will in effect assume a substantially barrel-shaped configuration, as is shown exaggerated in FIG. 10a. The edges of the hole, that is, the lines at which the conductor foils and the pin are in engagement with each other, do not participate in the shrinkage so that the initially established electrical contact is maintained in spite of the deformation of the hole within the interior of the panel.

As previously explained, the pin part inserted into the mounting hole is formed by convolutes of a springy flat strip. Accordingly, the inserted pin part acts somewhat in the manner of a wound watch spring, and maintains its tension against the edge of the hole in the foil when due to shrinkage the wall of the mounting hole pulls away from the inserted pin part.

As pin part 51 protrudes from the circuit board in its entirety and hence retains its resiliency, it may be advantageously used as male contact element for a rigid female contact sleeve such as sleeve 44 of FIG. 9 to effect an external spring-loaded connection with foil terminal 54.

Referring now to FIG. 11, this figure shows a blank 55 slotted and scored for winding pins of the type shown in FIGS. 8, 10, 10a and 11. There is indicated a trim line A. The blank has a lengthwise slot 56 to permit winding or rolling of a pin with two parts having different diameters. Assuming now that the blank is cut along lines B B and is then rolled, pins of the types shown in FIG. 8 are obtained. Depending upon the winding tension applied to the two parts of the blank defined by slot 56, either a double pin firmly wound at one part and loosely wound at the other part can be obtained, or an evenly wound double pin.

FIGS. 12 and 13 show a printed circuit connector 65 for connecting a printed circuit board 66 to external circuit components or a source of current (not shown).

The printed circuit board as diagrammatically indicated comprises an insulation panel 67 on which is formed on both sides as shown, or only on one side, a circuit pattern by a suitable printed circuit technique such as etching; more specifically, a number of foil conducts ending in terminals 68 to be connected to connector 65 are shown.

The connector comprises a channeled insulation body 69. As can be clearly seen in FIG. 12, the channel is stepped to defined upper level channel parts 69a and a lower level channel part 69b. The upper channel parts have a plurality of holes therethrough and constitute seating surfaces for a plurality of double pins 70 of the general type shown in FIG. 8. The narrow part 71 of each pin is extended through one of the holes in seating surfaces 69a and is anchored in the insulation body by spring pressure, as described in connection with F IG. 9. The wide part 72 of each pin protrudes from the respective seating surface 69a.

The maximal diameter of each wide pin part 72 is such that the pin part slightly overhangs the lower level channel part 6%, as is clearly shown in FIG. 3 for the two right hand end pins 70.

To connect the printed circuit board 66 to connector 65, the part of panel 67 bearing terminals 68is forced into the lower level channel part 69b in a position such that each of the terminals to be connected is in registry with the protruding part 72 of one of the double pins. As it is clearly apparent from FIG. 13, the terminals will engage the respective pin parts 72 with a frictional pressure engagement causing, as shown, a slight flattening of the pins engaged by terminals, thereby assuring good and stable contact conditions. Disconnection of the printed circuit board is effected by simply pulling the same out of channel part 6% and out of engagement with parts 72 of the double pins.

The pin parts 71 protruding from the base of insulation body 69 can be used as male or female connector elements, as has been described in connection with FIG. 9. As is evident, any number of connections can be made by means of connector 65 in a convenient and reliable manner.

FIG. 14 shows a double pin 60 of the kind shown in FIG. 8 and used as a mechanical fastener. The pin has parts 36 and 37 wound with different diameters. One part of the pin such as part 36 is inserted into a confining mounting hole of a base member 38 and the other into a confining mounting hole of a member 39, thereby detachably joining the two members. Member 39 may be visualized as an ornamental element such as a bead of a piece of jewelry, and base 38 may be visualized as another piece of jewelry constituting a support for the bead. As previously described in connection with the use of double pins as circuit components, the pin is preferably so wound that the spring tension of the pin part which is to remain in its member when the two members are separated is the higher one. The resulting higher retention force of this spring part insures that the pin always remains in the selected member such as the base 38 when the bead is pulled out of its pin part.

What is claimed is:

l. A connector assemblage comprisingin combination:

a generally cylindrical sleeve for insertion into a confining mounting hole in a support, said sleeve constituting a receiving contact member of the assemblage and being formed of a spirally rolled springy metal strip having several convolutes in engagement with each other at adjacent surfaces, the inner end of said strip protruding inwardly to form an elastic tongue extending substantially crosswise within the sleeve, said tongue defining two chambers within the sleeve along the length thereof,

said sleeve havi extendin i wardl from o e of its ends a notch f gr accomm o ating therein a bentoff elongate member inserted into the sleeve; and

a wire conductor insertable into either one of said chambers and having a peripheral outline engaging an inner wall portion of the sleeve and a wall portion of the tongue with pressure contact upon insertion of the conductor into said one chamber, said wire conductor constituting an engaging contact member of the assemblage.

2. The connector assemblage according to claim 1 wherein said tongue has a substantially S-shaped cross section and terminates short of the inner wall of the sleeve.

3. A hollow generally cylindrical pin for insertion into confining mounting holes in support members, said pin having two lengthwise contiguous independently springy rolled parts of different diameter, either one of said parts being adapted to be inserted into a confining mounting hole of a support member, one of said pin parts being rolled tighter than the other whereby upon insertion of the pin parts into the mounting holes of two support members the tighter rolled pin part is retained in the respective one of said members with a stronger retention force than the other pin part in the other member.

4. The pin according to claim 3 wherein the end portions of said sheet metal strip overlap each other, the outer end portion of the pin being bent off to form a contact flag. 

1. A connector assemblage comprising in combination: a generallY cylindrical sleeve for insertion into a confining mounting hole in a support, said sleeve constituting a receiving contact member of the assemblage and being formed of a spirally rolled springy metal strip having several convolutes in engagement with each other at adjacent surfaces, the inner end of said strip protruding inwardly to form an elastic tongue extending substantially crosswise within the sleeve, said tongue defining two chambers within the sleeve along the length thereof, said sleeve having extending inwardly from one of its ends a notch for accommodating therein a bent-off elongate member inserted into the sleeve; and a wire conductor insertable into either one of said chambers and having a peripheral outline engaging an inner wall portion of the sleeve and a wall portion of the tongue with pressure contact upon insertion of the conductor into said one chamber, said wire conductor constituting an engaging contact member of the assemblage.
 2. The connector assemblage according to claim 1 wherein said tongue has a substantially S-shaped cross section and terminates short of the inner wall of the sleeve.
 3. A hollow generally cylindrical pin for insertion into confining mounting holes in support members, said pin having two lengthwise contiguous independently springy rolled parts of different diameter, either one of said parts being adapted to be inserted into a confining mounting hole of a support member, one of said pin parts being rolled tighter than the other whereby upon insertion of the pin parts into the mounting holes of two support members the tighter rolled pin part is retained in the respective one of said members with a stronger retention force than the other pin part in the other member.
 4. The pin according to claim 3 wherein the end portions of said sheet metal strip overlap each other, the outer end portion of the pin being bent off to form a contact flag. 